// Copyright 2021 EMQ Technologies Co., Ltd.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package planner

import "github.com/lf-edge/ekuiper/v2/internal/pkg/def"

type logicalOptRule interface {
	optimize(LogicalPlan, *def.RuleOption) (LogicalPlan, error)
	name() string
}

type predicatePushDown struct{}

func (r *predicatePushDown) optimize(lp LogicalPlan, _ *def.RuleOption) (LogicalPlan, error) {
	_, p := lp.PushDownPredicate(nil)
	return p, nil
}

func (r *predicatePushDown) name() string {
	return "predicatePushDown"
}

type columnPruner struct{}

func (r *columnPruner) optimize(lp LogicalPlan, _ *def.RuleOption) (LogicalPlan, error) {
	err := lp.PruneColumns(nil)
	return lp, err
}

func (r *columnPruner) name() string {
	return "columnPruner"
}
